Pre-stressed tie guard with knife section retainer

ABSTRACT

A sickle guard having separable upper and lower sections, the both sections, which are pre-stressed, oppose excessive lateral as well as longitudinal loads due to the guards striking obstructions or the sickle being deflected out of plane and striking the upper section. A novel wedging action is obtained between the sections which is conducive to a favorable destribution of the forces opposing destructive loads.

United States Patent Scamato et a1.

[ 1 Oct. 24, 1972 [541 PRE-STRESSED TIE GUARD WITH KNIFE SECTION RETAINER [72] Inventors: Thomas J. Scamato, Barrington; Peter J. Peacock, Western Springs; John J. Kowalik, Glenview, all of I11.

[73] Assignee: International Harvester Company,

Chicago, 111.

221 Filed: Feb. 25, 1972 [211 Appl. No.: 229,449

521 11s. 01 ..56/307 51] Int. Cl. ..A0ld 55/10 [58] Field of Search ..so/29o-313 [56] References Cited UNITED STATES PATENTS 13,433 8/1855 Morrison ..so/305 x 642,485 1/1900 Pierson ..5o/29o 1,085,349 1/1914 Likely ..56/298 1,185,442 Southwick ..56/310 2,246,943 6/1941 Jones ..56/298 3,151,434 10/1964 Hamel ..56/296 3,314,222 4/ 1967 Scamato et a1 ..56/305 3,490,215 1/ 1970 Chapman et al ..56/298 3,553,948 1/1971 White ..56/307 FOREIGN PATENTS OR APPLICATIONS 121,473 i 11/1927 Switzerland ..56/310 Primary Examiner-Russell R. Kinsey Attorney-Floyd B. Harman [57] ABSTRACT A sickle guard having separable upper and lower sections, the both sections, which are pre-stressed, oppose excessive lateral as well as longitudinal loads due to the guards striking obstructions or the sickle being deflected out of plane and striking the upper section. A novel wedging action is obtained between the sections which is conducive to a favorable destribution of the forces opposing destructive loads.

11 Claims, 5 Drawing Figures PRE-STRESSED TIE GUARD WITH KNIFE SECTION RETAINER DISCUSSION OF THE PRIOR ART In prior art devices exemplified principally in US. Pat. Nos. 3,553,948 and 3,490,215, the upper and lower sections are interlocked at their forward ends in 7 SUMMARY OF THE INVENTION This invention is concerned with a novel arrangement of mower guard sections which are interlocked to mutually resist various destructive loadings.

A general object is to provide an arrangement of upper and lower sections of a mower guard assembly wherein said sections are preloaded in opposition to anticipate destructive loads.

A more specific object is to provide a lower sickle supporting guard section and an upper overlying guide and reinforcing tie section wherein the upper section is in the form of a resilient steel strap which has a pair of guide elements overlying a pair of guard fingers and the fingers and guide elements provided with a wedging interlock which holds the sections in alignment and obtains an exceptionally strong assembly.

These and other objects and advantages inherent in the invention will become more apparent from the specifications and the drawings wherein:

FIG. 1 is a fragmentary top plan view of a mower incorporating the invention;

FIG. 2 is an enlarged longitudinal sectional view taken substantially on line 2-2 of FIG. 1;

FIG. 3 is a cross-sectional view taken substantially on line 3-3 of FIG. 2; and

FIG. 4 is a fragmentary elongated view partly in section taken substantially on line 4-4 of FIG. 2; and

FIG. 5 is a fragmentary side elevational view of the parts in preassembled position.

DESCRIPTION OF THE INVENTION In the drawings, there is shown a novel mower or cutter construction generally designated 2 comprising a support structure 3 herein shown as part of a deck of a harvesting machine. However, the invention is equally applicable to a mower with a conventional mower bar as well known to those skilled in the art.

,The support overlaps the rear anchor portions or eye structures 4 of the bottom sections 5 of guard assemblies generally designated 5'. Each guard assembly 5 is a bilaterally symmetrical structure and each side of the bottom section 5 thereof comprises a fore and aft elongated relatively thin or narrow finger portion 6 having an intermediate body 7 with a bottom sole surface 8 and a top platform or sickle-opposing surface 9 of generally trapezodial form. The surface 9 may support a ledger plate or, as in the present instance, may form with the sides 10 and 11 (FIG. 3) of the body portion sharp cutting edges 12 and 13.

Each body portion 7 is integrally connected at its rear end with the respective anchor or securing portion 4 and the fingers are interconnected at the junction of the body and securing portions by a transversely extending spanner or deflector rib or bar 15 (FIG. 1) which forms the forward edge portion of a channel or groove 16 for receiving a backing or connecting bar 17 of a sickle generally designated 18.

The sickle comprises a plurality of triangular sickle sections or blades 20 secured at the rear base portions 21 as by rivets 22 to the bar 17 which rides in the channel16.

The channel 16 has a bottom wall or web 24 which is below the level of the platform surface 9 and the channel 16 is deep enough to accommodate the bottom rivet heads 25 (FIG. 2) of the rivets 22. The anchor side of the channel is defined by an upstanding guide or abutment bar or rib 27 which has its back side 28 (FIG. 2) abutting the forward edge 29 of the support structure.

It will be seen from FIG; 1 that the bar 15 has end portions 30 which are coplanar therewith and serve as spacers and at their oppose the end portions 30 of the adjacent guards so that the front edge of the channel is continuous from one end of the mower to the other. The ribs 27 on the back side of the channel terminate flush with the side edges 32 of the interconnected anchor portions of the guard. Thus, dirt exit openings 33 (FIG. I) are provided for sifting debris and dirt through the bottom.

The fingers are each provided with a forward pointed end portion or node 35 which has an upwardly curving bottom edge 36 terminating in a point 37. The upper side 38 of each node is essentially fiat and projects upwardly and rearwardly into a lip or wedge projection 40 which has a rearwardly facing wedge surface 41 on its underside sloping downwardly and forwardly in converging relation to the top surface 9 at about a 45 angle.

Each guard assembly includes an upper section clip or tie member 45 which is preferably-stamped from about It; to 9/64 inch sheet steel plate and is generally H-shaped in top plan view and mates with the lower section 5 of the guard assembly which is preferably made of forged steel. The tie member 45 comprises a pair of guide elements 46 which are each slightly narrower than the width of the platform surface 9 therebeneath and laterally centered with respect thereto.

Each guide element 46 has a forward end wedge portion or flange 47 bent generally non-parallel with the respective wedge surface 41 and on its top or forward side 48 is in tight engagement therewith. Preferably the surface 41 is disposed at an angle of 45 to surface 9 and surface 48 in preassembled position of tie element 45 with guard portion 5' is disposed at a 44 angle to surface 9 as seen in FIG. 5. Surface 48 is related to top surface 48' of finger 46 at an angle of l36, it being understood that these surfaces may be at .the same angle and fall within the scope of the invention, but in order to obtain a higher stress loading on the assembly the angle of the lip and flange should be different, that is the angle on the lip must be greater than the angle on the mating flange. More specifically, the angle of surface 41 to surface 9 may be 45 or more and the angle or surface 48 would be always slightly smaller.

As best seen in FIG. 5 angle a 6 such that in preassembled position the guide element 45 is angled upwardly and rearwardly and when drawn down bows portion 46 upwardly and the deflection of finger 46 permits surface 48 to conform to the face 41 and stress loads the finger 46 in bend and compression and portion 7 principally in tension. The lower end 49 of the wedge portion contacts the forward end of the platform surface 9. Adjacent to their rear ends 51, the guide elements are interconnected by a bracing or interconnecting bar 52 extending therebetween above the bar substantially in vertical alignment therewith.

Rearwardly of the bar 52 of the guide elements, the tie structure is provided with arcuate segments or humps 54 which are bowed upwardly sufficiently to clear the upper heads 55 of the rivets. The hump portions 54 are wider than the guide elements and they merge into knife-hold-down offsets 56 which, in turn, merge into rearwardly extending anchor securing or eye portions 57 which gradually widen toward a rear edge 57' and are below the offsets 56 and connected therewith by intervening shoulders 58.

As best seen in FIG. 2, each ofiset 56 bears against the top edge 60 of the adjacent sickle blade which rests as at 61 against the top side 62 of a wear plate guide 63, which plate 63 has a depending front flange 64 abutting against the rear edge 65 of the knife backing bar. The guide plate 63 is apertured with bolt holes 66 and each hole 66 aligns with associated holes 67,68 in the support parts and a hole 69 in the respective anchor portion 4 and these holes receive a bolt shank 70 therethrough which has a lower end head 71 depressed into a recess 72 about hole 69. Each bolt shank 70 extends through an opening or hole 73 in the related securing portion 57 of the upper section. A nut 74 is threaded onto the upper end of shank 70 and draws the parts into a tight assembly.

It will be understood that in unstressed condition, the distance from opening 73 to the area of engagement of flange 47 with respective surface 41 is greater than the distance between the opening 69 and the respective surface 41 whereby in assembling the top section and tightening up the nuts, guide portions 46 flex slightly upwardly thereby preloading them and slightly enlarging the knife accommodation slot 75 between each guide element and the platform surface therebetween. The loading is directed toward the forward pointed end portions of the fingers and resist upward thrusts on the points.

lt'will be understood that in assembling element 45 with the bottom sections 5, the element 45 is disposed in an upwardly and rearwardly sloping position and flanges 47 are hooked under the lips 40 and then the bolts are applied and the element 45 drawn down. Thus the portions 46 are bowed slightly upwardly and the greater the angular difference between flange surface 48 and surface 41, the greater the preload.

Lateral impacts due to a deflected knife 20 or foreign material entering between sections 5 and the knife are accommodated by the guide elements 46 flexing laterally under impact while sliding along the aforesaid wedge areas without the parts breaking. These portions 46 will normally bend and in extreme cases will slide out from under the lips without breaking off the guard tips or points. Also in some instances the least expensive part, the sickle knife section 20 will break or shear off the rivets while the guide portion is slightly deflected.

It will be appreciated that a novel and effective guard assembly has been provided with due regard having been had to provide strength in areas of concentrated loading and preloading the assembly in directions to effectively counter the loadings encountered in ordinary use.

What is claimed is:

1. In a mower of the type having a support bar, a plurality of guards mounted thereon, and a sickle having a shearing relationship with the guards, the improvement comprising:

a. each guard having a body projecting forwardly from the bar,

a sickle opposing platform surface on the body and having means providing shearing edges cooperatively associated with the sickle,

c. said body having a front end portion with a rearwardly directed ramp overhanging the platform surface,

. a wedge surface on said ramp converging with said platform surface toward said front end portion, and

e. a resilient tie clip having a guide portion spaced from the platform surface to provide a sickle-accommodating space therewith and having a front end section in wedging engagement with said wedge surface.

2. The invention according to claim 1 and said guard having a plurality of laterally spaced interconnected bodies, and said tie clip having a plurality of said guide portions one associated with each body, and means interconnecting said guide portions.

3. The invention according to claim 1 and said tie clip being preloaded between said bar and said ramp with said guide portion bulged slightly away from the surface and effective to resist loads imposed upon the front end portion of the guard upon striking an obstruction.

4. For a mower of the type having a nonnally horizontally positioned support bar and guards projecting forwardly from the bar and a sickle reciprocal on the guards, each guard structure comprising:

a. an elongated finger having a pointed front end portion with an upper side and a rear anchor portion for securement to the bar and having a platform surface on the finger,

. a projection extending rearwardly from the upper side of said forward end portion and providing a rearwardly facing wedge surface converging downwardly and forwardly with the platform surface, and

. a combination guide and reinforcing bracket of resilient material, said bracket having a narrow guide portion overlying the platform and tenninating in a rear end attachment portion and having a flange at its forward end angled downwardly and forwardly and in wedge engagement with said wedge surface, said guide portion being stressed to preload said finger in opposition to forces induced by the guard striking an obstruction.

5. The invention according to claim 4 and said flange providing a wedge surface at a slightly different angle than said wedge surface on said projection.

6. The invention according to claim 4 and said guard comprising a pair of identical transversely spaced fingets,

a. a bar interconnecting said fingers adjacent to the anchor portions thereof,

b. said bracket having a pair of said guide portions one for each finger with a front flange and a rear attachment portion,

c. a bar on each guide portion interconnecting said guide portions, and

d. a transverse tie member interconnecting said guide portions adjacent to said attachment portions.

7. A guard comprising a pair of laterally spaced narrow fingers each having a pointed front end portion and a rear end anchor portion, means interconnecting said fingers in the areas of the junctures of the fingers with the anchor portions, said fingers having coplanar platform surfaces on one side extending from adjacent to the front end portion to adjacent the anchor portion, a lip projection of the front end portion of each finger overhanging a portion of the respective platform surface adjacent to the front end portion, and a wedge surface on both lip projections converging at an angle of approximately 45 with the opposing associated platform surface toward the front end portion whereby the transverse section of the lip projection increases toward its juncture with the forward end portion.

8. A guard comprising a pair of laterally spaced narrow fingers each having a pointed front end portion and a rear end anchor portion, means interconnecting said fingers in the areas of the junctures of the fingers with the anchor portions, said fingers having coplanar platform surfaces on one side extending from adjacent to the front end portion to adjacent the anchor portion, a lip projection on the front end portion of each finger overhanging a portion of the respective platform surface adjacent to the front end portion, a wedge surface on the lip projections converging with the opposing associated platform surface toward the front end portion whereby the transverse section of the lip portion increases toward its juncture with the forward end portion, a guide and securing clip comprising a pair of relatively thin, resilient metal guide members spaced to align with respective fingers and opposing respective platform surfaces thereon and of a width approximately that of the associated finger, each guide member having a forward end portion angled substantially parallel with and for engaging an opposing wedge surface, a bar interconnecting said guide members adjacent to their rear ends, and securing means integral with the guide members and extending rearwardly therefrom.

9. The invention according to claim 8 and each guide member having an upwardly bowed sickle-bar-rivet clearing hump adjacent the rear end thereof and an offset sickle section retainer portion between the hump and the securing means.

' 10. The invention according to claim 9 and said interconnecting bar located adjacent to the forward ends of the humps.

11. The invention according to claim 10 and said clip being formed of steel and said finger members being located in a plane offset from the plane of the securing means and the contour of the clip in edge elevation being conducive to upward bowing thereof attendant to loading of the clip between the securing means and the wedge surfaces. 

1. In a mower of the type having a support bar, a plurality of guards mounted thereon, and a sickle having a shearing relationship with the guards, the improvement comprising: a. each guard having a body projecting forwardly from the bar, b. a sickle opposing platform surface on the body and having means providing shearing edges cooperatively associated with the sickle, c. said body having a front end portion with a rearwardly directed ramp overhanging the platform surface, d. a wedge surface on said ramp converginG with said platform surface toward said front end portion, and e. a resilient tie clip having a guide portion spaced from the platform surface to provide a sickle-accommodating space therewith and having a front end section in wedging engagement with said wedge surface.
 2. The invention according to claim 1 and said guard having a plurality of laterally spaced interconnected bodies, and said tie clip having a plurality of said guide portions one associated with each body, and means interconnecting said guide portions.
 3. The invention according to claim 1 and said tie clip being preloaded between said bar and said ramp with said guide portion bulged slightly away from the surface and effective to resist loads imposed upon the front end portion of the guard upon striking an obstruction.
 4. For a mower of the type having a normally horizontally positioned support bar and guards projecting forwardly from the bar and a sickle reciprocal on the guards, each guard structure comprising: a. an elongated finger having a pointed front end portion with an upper side and a rear anchor portion for securement to the bar and having a platform surface on the finger, b. a projection extending rearwardly from the upper side of said forward end portion and providing a rearwardly facing wedge surface converging downwardly and forwardly with the platform surface, and c. a combination guide and reinforcing bracket of resilient material, said bracket having a narrow guide portion overlying the platform and terminating in a rear end attachment portion and having a flange at its forward end angled downwardly and forwardly and in wedge engagement with said wedge surface, said guide portion being stressed to preload said finger in opposition to forces induced by the guard striking an obstruction.
 5. The invention according to claim 4 and said flange providing a wedge surface at a slightly different angle than said wedge surface on said projection.
 6. The invention according to claim 4 and said guard comprising a pair of identical transversely spaced fingers, a. a bar interconnecting said fingers adjacent to the anchor portions thereof, b. said bracket having a pair of said guide portions one for each finger with a front flange and a rear attachment portion, c. a bar on each guide portion interconnecting said guide portions, and d. a transverse tie member interconnecting said guide portions adjacent to said attachment portions.
 7. A guard comprising a pair of laterally spaced narrow fingers each having a pointed front end portion and a rear end anchor portion, means interconnecting said fingers in the areas of the junctures of the fingers with the anchor portions, said fingers having coplanar platform surfaces on one side extending from adjacent to the front end portion to adjacent the anchor portion, a lip projection of the front end portion of each finger overhanging a portion of the respective platform surface adjacent to the front end portion, and a wedge surface on both lip projections converging at an angle of approximately 45* with the opposing associated platform surface toward the front end portion whereby the transverse section of the lip projection increases toward its juncture with the forward end portion.
 8. A guard comprising a pair of laterally spaced narrow fingers each having a pointed front end portion and a rear end anchor portion, means interconnecting said fingers in the areas of the junctures of the fingers with the anchor portions, said fingers having coplanar platform surfaces on one side extending from adjacent to the front end portion to adjacent the anchor portion, a lip projection on the front end portion of each finger overhanging a portion of the respective platform surface adjacent to the front end portion, a wedge surface on the lip projections converging with the opposing associated platform surface toward the front end portion whereby the transverse section of the lip portion increases toward its jUncture with the forward end portion, a guide and securing clip comprising a pair of relatively thin, resilient metal guide members spaced to align with respective fingers and opposing respective platform surfaces thereon and of a width approximately that of the associated finger, each guide member having a forward end portion angled substantially parallel with and for engaging an opposing wedge surface, a bar interconnecting said guide members adjacent to their rear ends, and securing means integral with the guide members and extending rearwardly therefrom.
 9. The invention according to claim 8 and each guide member having an upwardly bowed sickle-bar-rivet clearing hump adjacent the rear end thereof and an offset sickle section retainer portion between the hump and the securing means.
 10. The invention according to claim 9 and said interconnecting bar located adjacent to the forward ends of the humps.
 11. The invention according to claim 10 and said clip being formed of steel and said finger members being located in a plane offset from the plane of the securing means and the contour of the clip in edge elevation being conducive to upward bowing thereof attendant to loading of the clip between the securing means and the wedge surfaces. 